Fixes https://matrix.org/jira/browse/SPEC-429.
Synapse currently follows the specified ordering, but does *not* give the
specified error when the state is invalid (instead it creates the room anyway
but gives a 403 M_FORBIDDEN). Still, I don't think that should be a real
problem for any real clients, and nothing would break if we changed this in
synapse, so it might as well go in the spec anyway.
We're licensing hte spec under ASLv2. Add the LICENSE file, and add the
short-form to as much of the source as is practical right now (adding it to
json source is a massive pita).
As a side effect, I got rid of all of the horrible symlinks and just put
in all of the proper relative paths. Because the horrible symlinks were
horrible.